/usr/lib/linux-tools/4.15.0-23-lowlatency/cpupower is in linux-tools-4.15.0-23-lowlatency 4.15.0-23.25~16.04.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/linux-tools/4.15.0-23-lowlatency/../../linux-hwe-edge-tools-4.15.0-23/cpupower